A275602 The concatenation of |a(n)-a(n+1)| and a(n+1) is prime and all such concatenations are different one from another. Terms are distinct.

1, 3, 7, 9, 11, 17, 21, 23, 13, 19, 27, 29, 33, 47, 39, 41, 31, 57, 61, 37, 43, 63, 67, 53, 49, 51, 59, 69, 71, 77, 83, 79, 73, 81, 91, 87, 97, 109, 89, 101, 111, 113, 99, 1037, 121, 107, 93, 103, 123, 127, 129, 131, 119, 1023, 1031, 117, 1039, 133, 1009, 153, 157, 141, 143, 139, 137, 149, 159, 161, 151, 163, 171

Offset

1,2

Comments

The sequence starts with a(1) = 1 and is always extended with the smallest integer not yet present that does not lead to a contradiction.

This sequence is conjectured to be a permutation of the odd integers not ending with the digit “5”.

This sequence is a variant of A275386 and shares with it the first 900 terms.

Links

Jean-Marc Falcoz, Table of n, a(n) for n = 1..5474

Example

1,3,7,9,11,17,21,23,13,19,27,29,
|1-3| = 2 and 23 is prime; |3-7| = 4 and 47 is prime; |7-9| = 2 and 29 is prime; |9-11| = 2 and 211 is prime; |11-17| = 6 and 617 is prime; etc.

Crossrefs

Cf. A275386.

Sequence in context: A075607 A256465 A275386 * A173699 A287202 A156770

Adjacent sequences: A275599 A275600 A275601 * A275603 A275604 A275605

Keyword

nonn,base

Author

Eric Angelini and Jean-Marc Falcoz, Nov 14 2016

Status

approved